BSD is an acronym for Berkeley Software Distribution which is a version of the Unix operating system that was independently developed by the University of California, Berkeley computer science faculty and graduate students, as well as participants in a widespread open-source development project called the Berkeley Software Distribution (BSD). AT&T, where Unix originated, helped to initiate Unix by providing the source code to Berkeley and other university researchers; subsequently, it participated in Unix development and incorporated Unix innovations into what would later become its commercial version of Unix, called System V. See FreeBSD, open-source software (OSS), TCP/IP, Unix.